/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/****************************************************************************
 * fs/romfs/fs_romfs.c
 *
 *   Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * References: Linux/Documentation/filesystems/romfs.txt
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <tinyara/config.h>

#include <sys/types.h>
#include <sys/statfs.h>
#include <sys/stat.h>

#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <limits.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>

#include <tinyara/kmalloc.h>
#include <tinyara/fs/fs.h>
#include <tinyara/fs/ioctl.h>
#include <tinyara/fs/dirent.h>

#include "fs_romfs.h"

/****************************************************************************
 * Private Types
 ****************************************************************************/

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

static int romfs_open(FAR struct file *filep, FAR const char *relpath, int oflags, mode_t mode);
static int romfs_close(FAR struct file *filep);
static ssize_t romfs_read(FAR struct file *filep, FAR char *buffer, size_t buflen);
static off_t romfs_seek(FAR struct file *filep, off_t offset, int whence);
static int romfs_ioctl(FAR struct file *filep, int cmd, unsigned long arg);

static int romfs_dup(FAR const struct file *oldp, FAR struct file *newp);
static int romfs_fstat(FAR const struct file *filep, FAR struct stat *buf);

static int romfs_opendir(FAR struct inode *mountpt, FAR const char *relpath, FAR struct fs_dirent_s *dir);
static int romfs_readdir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir);
static int romfs_rewinddir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir);

static int romfs_bind(FAR struct inode *blkdriver, FAR const void *data, FAR void **handle);
static int romfs_unbind(FAR void *handle, FAR struct inode **blkdriver);
static int romfs_statfs(FAR struct inode *mountpt, FAR struct statfs *buf);

static int romfs_stat_common(uint8_t type, uint32_t size, uint16_t sectorsize, FAR struct stat *buf);
static int romfs_stat(FAR struct inode *mountpt, FAR const char *relpath, FAR struct stat *buf);

/****************************************************************************
 * Private Variables
 ****************************************************************************/

/****************************************************************************
 * Public Variables
 ****************************************************************************/

/* See fs_mount.c -- this structure is explicitly externed there.
 * We use the old-fashioned kind of initializers so that this will compile
 * with any compiler.
 */

const struct mountpt_operations romfs_operations = {
	romfs_open,					/* open */
	romfs_close,				/* close */
	romfs_read,					/* read */
	NULL,						/* write */
	romfs_seek,					/* seek */
	romfs_ioctl,				/* ioctl */

	NULL,						/* sync */
	romfs_dup,					/* dup */
	romfs_fstat,				/* fstat */
	NULL,						/* truncate */

	romfs_opendir,				/* opendir */
	NULL,						/* closedir */
	romfs_readdir,				/* readdir */
	romfs_rewinddir,			/* rewinddir */

	romfs_bind,					/* bind */
	romfs_unbind,				/* unbind */
	romfs_statfs,				/* statfs */

	NULL,						/* unlink */
	NULL,						/* mkdir */
	NULL,						/* rmdir */
	NULL,						/* rename */
	romfs_stat					/* stat */
};

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: romfs_open
 ****************************************************************************/

static int romfs_open(FAR struct file *filep, FAR const char *relpath, int oflags, mode_t mode)
{
	struct romfs_dirinfo_s dirinfo;
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_file_s *rf;
	int ret;

	fvdbg("Open '%s'\n", relpath);

	/* Sanity checks */

	DEBUGASSERT(filep->f_priv == NULL && filep->f_inode != NULL);

	/* Get mountpoint private data from the inode reference from the file
	 * structure
	 */

	rm = (FAR struct romfs_mountpt_s *)filep->f_inode->i_private;

	DEBUGASSERT(rm != NULL);

	/* Check if the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret != OK) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* ROMFS is read-only.  Any attempt to open with any kind of write
	 * access is not permitted.
	 */

	if ((oflags & O_WRONLY) != 0 || (oflags & O_RDONLY) == 0) {
		fdbg("Only O_RDONLY supported\n");
		ret = -EACCES;
		goto errout_with_semaphore;
	}

	/* Initialize the directory info structure */

	memset(&dirinfo, 0, sizeof(struct romfs_dirinfo_s));

	/* Locate the directory entry for this path */

	ret = romfs_finddirentry(rm, &dirinfo, relpath);
	if (ret < 0) {
		fdbg("Failed to find directory directory entry for '%s': %d\n", relpath, ret);
		goto errout_with_semaphore;
	}

	/* The full path exists -- but is the final component a file
	 * or a directory?
	 */

	if (IS_DIRECTORY(dirinfo.rd_next)) {
		/* It is a directory */

		ret = -EISDIR;
		fdbg("'%s' is a directory\n", relpath);
		goto errout_with_semaphore;
	} else if (!IS_FILE(dirinfo.rd_next)) {
		/* ENXIO indicates "The named file is a character special or
		* block special file, and the device associated with this
		* special file does not exist."
		*
		* Here we also return ENXIO if the file is not a directory
		* or a regular file.
		*/

		ret = -ENXIO;
		fdbg("ERROR: '%s' is a special file\n", relpath);
		goto errout_with_semaphore;
	}
#ifdef CONFIG_FILE_MODE
#warning "Missing check for privileges based on inode->i_mode"
#endif

	/* Create an instance of the file private data to describe the opened
	 * file.
	 */

	rf = (FAR struct romfs_file_s *)kmm_zalloc(sizeof(struct romfs_file_s));
	if (!rf) {
		fdbg("Failed to allocate private data\n", ret);
		ret = -ENOMEM;
		goto errout_with_semaphore;
	}

	/* Initialize the file private data (only need to initialize
	 * non-zero elements)
	 */

	rf->rf_size = dirinfo.rd_size;
	rf->rf_type = (uint8_t)(dirinfo.rd_next & RFNEXT_ALLMODEMASK);

	/* Get the start of the file data */

	ret = romfs_datastart(rm, dirinfo.rd_dir.fr_curroffset, &rf->rf_startoffset);
	if (ret < 0) {
		fdbg("Failed to locate start of file data: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Configure buffering to support access to this file */

	ret = romfs_fileconfigure(rm, rf);
	if (ret < 0) {
		fdbg("Failed configure buffering: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Attach the private date to the struct file instance */

	filep->f_priv = rf;

	/* Then insert the new instance into the mountpoint structure.
	 * It needs to be there (1) to handle error conditions that effect
	 * all files, and (2) to inform the umount logic that we are busy
	 * (but a simple reference count could have done that).
	 */

	rf->rf_next = rm->rm_head;
	rm->rm_head = rf->rf_next;

	romfs_semgive(rm);
	return OK;

	/* Error exits */

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_close
 ****************************************************************************/

static int romfs_close(FAR struct file *filep)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_file_s *rf;
	int ret = OK;

	fvdbg("Closing\n");

	/* Sanity checks */

	DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL);

	/* Recover our private data from the struct file instance */

	rf = filep->f_priv;
	rm = filep->f_inode->i_private;

	DEBUGASSERT(rm != NULL);

	/* Do not check if the mount is healthy.  We must support closing of
	 * the file even when there is healthy mount.
	 */

	/* Deallocate the memory structures created when the open method
	 * was called.
	 *
	 * Free the sector buffer that was used to manage partial sector
	 * accesses.
	 */

	if (!rm->rm_xipbase && rf->rf_buffer) {
		kmm_free(rf->rf_buffer);
	}

	/* Then free the file structure itself. */

	kmm_free(rf);
	filep->f_priv = NULL;
	return ret;
}

/****************************************************************************
 * Name: romfs_read
 ****************************************************************************/

static ssize_t romfs_read(FAR struct file *filep, FAR char *buffer, size_t buflen)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_file_s *rf;
	unsigned int bytesread;
	unsigned int readsize;
	unsigned int nsectors;
	uint32_t offset;
	size_t bytesleft;
	off_t sector;
	FAR uint8_t *userbuffer = (FAR uint8_t *)buffer;
	int sectorndx;
	int ret;

	fvdbg("Read %d bytes from offset %d\n", buflen, filep->f_pos);

	/* Sanity checks */

	DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL);

	/* Recover our private data from the struct file instance */

	rf = filep->f_priv;
	rm = filep->f_inode->i_private;

	DEBUGASSERT(rm != NULL);

	/* Make sure that the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret != OK) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Get the number of bytes left in the file */

	bytesleft = rf->rf_size - filep->f_pos;

	/* Truncate read count so that it does not exceed the number
	 * of bytes left in the file.
	 */

	if (buflen > bytesleft) {
		buflen = bytesleft;
	}

	/* Loop until either (1) all data has been transferred, or (2) an
	 * error occurs.
	 */

	readsize = 0;
	while (buflen > 0) {
		/* Get the first sector and index to read from. */

		offset = rf->rf_startoffset + filep->f_pos;
		sector = SEC_NSECTORS(rm, offset);
		sectorndx = offset & SEC_NDXMASK(rm);
		bytesread = 0;

		/* Check if the user has provided a buffer large enough to
		 * hold one or more complete sectors -AND- the read is
		 * aligned to a sector boundary.
		 */

		nsectors = SEC_NSECTORS(rm, buflen);
		if (nsectors > 0 && sectorndx == 0) {
			/* Read maximum contiguous sectors directly to the user's
			 * buffer without using our tiny read buffer.
			 */

			/* Read all of the sectors directly into user memory */

			fvdbg("Read %d sectors starting with %d\n", nsectors, sector);
			ret = romfs_hwread(rm, userbuffer, sector, nsectors);
			if (ret < 0) {
				fdbg("romfs_hwread failed: %d\n", ret);
				goto errout_with_semaphore;
			}

			sector += nsectors;
			bytesread = nsectors * rm->rm_hwsectorsize;
		} else {
			/* We are reading a partial sector.  First, read the whole sector
			 * into the file data buffer.  This is a caching buffer so if
			 * it is already there then all is well.
			 */

			fvdbg("Read sector %d\n", sector);
			ret = romfs_filecacheread(rm, rf, sector);
			if (ret < 0) {
				fdbg("romfs_filecacheread failed: %d\n", ret);
				goto errout_with_semaphore;
			}

			/* Copy the partial sector into the user buffer */

			bytesread = rm->rm_hwsectorsize - sectorndx;
			if (bytesread > buflen) {
				/* We will not read to the end of the buffer */

				bytesread = buflen;
			} else {
				/* We will read to the end of the buffer (or beyond) */

				sector++;
			}

			fvdbg("Return %d bytes from sector offset %d\n", bytesread, sectorndx);
			memcpy(userbuffer, &rf->rf_buffer[sectorndx], bytesread);
		}

		/* Set up for the next sector read */

		userbuffer += bytesread;
		filep->f_pos += bytesread;
		readsize += bytesread;
		buflen -= bytesread;
	}

	romfs_semgive(rm);
	return readsize;

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_seek
 ****************************************************************************/

static off_t romfs_seek(FAR struct file *filep, off_t offset, int whence)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_file_s *rf;
	off_t position;
	int ret;

	fvdbg("Seek to offset: %d whence: %d\n", offset, whence);

	/* Sanity checks */

	DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL);

	/* Recover our private data from the struct file instance */

	rf = filep->f_priv;
	rm = filep->f_inode->i_private;

	DEBUGASSERT(rm != NULL);

	/* Map the offset according to the whence option */

	switch (whence) {
	case SEEK_SET:				/* The offset is set to offset bytes. */
		position = offset;
		break;

	case SEEK_CUR:				/* The offset is set to its current location plus
								 * offset bytes. */

		position = offset + filep->f_pos;
		break;

	case SEEK_END:				/* The offset is set to the size of the file plus
								 * offset bytes. */

		position = offset + rf->rf_size;
		break;

	default:
		fdbg("Whence is invalid: %d\n", whence);
		return -EINVAL;
	}

	/* Make sure that the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret != OK) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Limit positions to the end of the file. */

	if (position > rf->rf_size) {
		/* Otherwise, the position is limited to the file size */

		position = rf->rf_size;
	}

	/* Set file position and return success */

	filep->f_pos = position;
	fvdbg("New file position: %d\n", filep->f_pos);

	romfs_semgive(rm);
	return OK;

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_ioctl
 ****************************************************************************/

static int romfs_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_file_s *rf;
	FAR void **ppv = (FAR void **)arg;

	fvdbg("cmd: %d arg: %08lx\n", cmd, arg);

	/* Sanity checks */

	DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL);

	/* Recover our private data from the struct file instance */

	rf = filep->f_priv;
	rm = filep->f_inode->i_private;

	DEBUGASSERT(rm != NULL);

	/* Only one ioctl command is supported */

	if (cmd == FIOC_MMAP && rm->rm_xipbase && ppv) {
		/* Return the address on the media corresponding to the start of
		 * the file.
		 */

		*ppv = (void *)(rm->rm_xipbase + rf->rf_startoffset);
		return OK;
	}

	fdbg("Invalid cmd: %d \n", cmd);
	return -ENOTTY;
}

/****************************************************************************
 * Name: romfs_dup
 ****************************************************************************/

static int romfs_dup(FAR const struct file *oldp, FAR struct file *newp)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_file_s *oldrf;
	FAR struct romfs_file_s *newrf;
	int ret;

	fvdbg("Dup %p->%p\n", oldp, newp);

	/* Sanity checks */

	DEBUGASSERT(oldp->f_priv != NULL && newp->f_priv == NULL && newp->f_inode != NULL);

	/* Get mountpoint private data from the inode reference from the file
	 * structure
	 */

	rm = (FAR struct romfs_mountpt_s *)newp->f_inode->i_private;
	DEBUGASSERT(rm != NULL);

	/* Check if the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret != OK) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Recover the old private data from the old struct file instance */

	oldrf = oldp->f_priv;

	/* Create an new instance of the file private data to describe the new
	 * dup'ed file.
	 */

	newrf = (FAR struct romfs_file_s *)kmm_malloc(sizeof(struct romfs_file_s));
	if (!newrf) {
		fdbg("Failed to allocate private data\n", ret);
		ret = -ENOMEM;
		goto errout_with_semaphore;
	}

	/* Copy all file private data (except for the buffer) */

	newrf->rf_startoffset = oldrf->rf_startoffset;
	newrf->rf_size = oldrf->rf_size;

	/* Configure buffering to support access to this file */

	ret = romfs_fileconfigure(rm, newrf);
	if (ret < 0) {
		fdbg("Failed configure buffering: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Attach the new private date to the new struct file instance */

	newp->f_priv = newrf;

	/* Then insert the new instance into the mountpoint structure.
	 * It needs to be there (1) to handle error conditions that effect
	 * all files, and (2) to inform the umount logic that we are busy
	 * (but a simple reference count could have done that).
	 */

	newrf->rf_next = rm->rm_head;
	rm->rm_head = newrf->rf_next;

	romfs_semgive(rm);
	return OK;

	/* Error exits */

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_fstat
 *
 * Description:
 *   Obtain information about an open file associated with the file
 *   pointer 'filep', and will write it to the area pointed to by 'buf'.
 *
 ****************************************************************************/

static int romfs_fstat(FAR const struct file *filep, FAR struct stat *buf)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_file_s *rf;
	int ret;

	fvdbg("fstat\n");

	/* Sanity checks */

	DEBUGASSERT(filep != NULL);
	DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL);
	DEBUGASSERT(buf != NULL);

	/* Get mountpoint private data from the inode reference from the file
	 * structure
	 */

	rf = filep->f_priv;
	rm = (FAR struct romfs_mountpt_s *)filep->f_inode->i_private;
	DEBUGASSERT(rm != NULL);

	/* Check if the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret >= 0) {
		/* Return information about the directory entry */

		ret = romfs_stat_common(rf->rf_type, rf->rf_size,
								rm->rm_hwsectorsize, buf);
	}

	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_opendir
 *
 * Description:
 *   Open a directory for read access
 *
 ****************************************************************************/

static int romfs_opendir(FAR struct inode *mountpt, FAR const char *relpath, FAR struct fs_dirent_s *dir)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_dirinfo_s dirinfo;
	int ret;

	fvdbg("relpath: '%s'\n", relpath);

	/* Sanity checks */

	DEBUGASSERT(mountpt != NULL && mountpt->i_private != NULL);

	/* Recover our private data from the inode instance */

	rm = mountpt->i_private;

	/* Make sure that the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret != OK) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Find the requested directory */

	ret = romfs_finddirentry(rm, &dirinfo, relpath);
	if (ret < 0) {
		fdbg("Failed to find directory '%s': %d\n", relpath, ret);
		goto errout_with_semaphore;
	}

	/* Verify that it is some kind of directory */

	if (!IS_DIRECTORY(dirinfo.rd_next)) {
		/* The entry is not a directory */

		fdbg("'%s' is not a directory: %d\n", relpath);
		ret = -ENOTDIR;
		goto errout_with_semaphore;
	}

	/* The entry is a directory */

	memcpy(&dir->u.romfs, &dirinfo.rd_dir, sizeof(struct fs_romfsdir_s));
	romfs_semgive(rm);
	return OK;

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_readdir
 *
 * Description: Read the next directory entry
 *
 ****************************************************************************/

static int romfs_readdir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir)
{
	FAR struct romfs_mountpt_s *rm;
	uint32_t linkoffset;
	uint32_t next;
	uint32_t info;
	uint32_t size;
	int ret;

	fvdbg("Entry\n");

	/* Sanity checks */

	DEBUGASSERT(mountpt != NULL && mountpt->i_private != NULL);

	/* Recover our private data from the inode instance */

	rm = mountpt->i_private;

	/* Make sure that the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret != OK) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Loop, skipping over unsupported items in the file system */

	for (;;) {
		/* Have we reached the end of the directory */

		if (!dir->u.romfs.fr_curroffset) {
			/* We signal the end of the directory by returning the
			 * special error -ENOENT
			 */

			fdbg("End of directory\n");
			ret = -ENOENT;
			goto errout_with_semaphore;
		}

		/* Parse the directory entry */

		ret = romfs_parsedirentry(rm, dir->u.romfs.fr_curroffset, &linkoffset, &next, &info, &size);
		if (ret < 0) {
			fdbg("romfs_parsedirentry failed: %d\n", ret);
			goto errout_with_semaphore;
		}

		/* Save the filename */

		ret = romfs_parsefilename(rm, dir->u.romfs.fr_curroffset, dir->fd_dir.d_name);
		if (ret < 0) {
			fdbg("romfs_parsefilename failed: %d\n", ret);
			goto errout_with_semaphore;
		}

		/* Set up the next directory entry offset */

		dir->u.romfs.fr_curroffset = next & RFNEXT_OFFSETMASK;

		/* Check the file type */

		if (IS_DIRECTORY(next)) {
			dir->fd_dir.d_type = DTYPE_DIRECTORY;
			break;
		} else if (IS_FILE(next)) {
			dir->fd_dir.d_type = DTYPE_FILE;
			break;
		}
	}

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_rewindir
 *
 * Description: Reset directory read to the first entry
 *
 ****************************************************************************/

static int romfs_rewinddir(FAR struct inode *mountpt, FAR struct fs_dirent_s *dir)
{
	FAR struct romfs_mountpt_s *rm;
	int ret;

	fvdbg("Entry\n");

	/* Sanity checks */

	DEBUGASSERT(mountpt != NULL && mountpt->i_private != NULL);

	/* Recover our private data from the inode instance */

	rm = mountpt->i_private;

	/* Make sure that the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret == OK) {
		dir->u.romfs.fr_curroffset = dir->u.romfs.fr_firstoffset;
	}

	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_bind
 *
 * Description: This implements a portion of the mount operation. This
 *  function allocates and initializes the mountpoint private data and
 *  binds the blockdriver inode to the filesystem private data.  The final
 *  binding of the private data (containing the blockdriver) to the
 *  mountpoint is performed by mount().
 *
 ****************************************************************************/

static int romfs_bind(FAR struct inode *blkdriver, FAR const void *data, FAR void **handle)
{
	struct romfs_mountpt_s *rm;
	int ret;

	fvdbg("Entry\n");

	/* Open the block driver */

	if (!blkdriver || !blkdriver->u.i_bops) {
		fdbg("No block driver/ops\n");
		return -ENODEV;
	}

	if (blkdriver->u.i_bops->open && blkdriver->u.i_bops->open(blkdriver) != OK) {
		fdbg("No open method\n");
		return -ENODEV;
	}

	/* Create an instance of the mountpt state structure */

	rm = (FAR struct romfs_mountpt_s *)kmm_zalloc(sizeof(struct romfs_mountpt_s));
	if (!rm) {
		fdbg("Failed to allocate mountpoint structure\n");
		return -ENOMEM;
	}

	/* Initialize the allocated mountpt state structure.  The filesystem is
	 * responsible for one reference ont the blkdriver inode and does not
	 * have to addref() here (but does have to release in ubind().
	 */

	sem_init(&rm->rm_sem, 0, 0);	/* Initialize the semaphore that controls access */
	rm->rm_blkdriver = blkdriver;	/* Save the block driver reference */

	/* Get the hardware configuration and setup buffering appropriately */

	ret = romfs_hwconfigure(rm);
	if (ret < 0) {
		fdbg("romfs_hwconfigure failed: %d\n", ret);
		goto errout_with_sem;
	}

	/* Then complete the mount by getting the ROMFS configuratrion from
	 * the ROMF header
	 */

	ret = romfs_fsconfigure(rm);
	if (ret < 0) {
		fdbg("romfs_fsconfigure failed: %d\n", ret);
		goto errout_with_buffer;
	}

	/* Mounted! */

	*handle = (void *)rm;
	romfs_semgive(rm);
	return OK;

errout_with_buffer:
	if (!rm->rm_xipbase) {
		kmm_free(rm->rm_buffer);
	}

errout_with_sem:
	sem_destroy(&rm->rm_sem);
	kmm_free(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_unbind
 *
 * Description: This implements the filesystem portion of the umount
 *   operation.
 *
 ****************************************************************************/

static int romfs_unbind(FAR void *handle, FAR struct inode **blkdriver)
{
	FAR struct romfs_mountpt_s *rm = (FAR struct romfs_mountpt_s *)handle;
	int ret;

	fvdbg("Entry\n");

#ifdef CONFIG_DEBUG
	if (!rm) {
		return -EINVAL;
	}
#endif

	/* Check if there are sill any files opened on the filesystem. */

	romfs_semtake(rm);
	if (rm->rm_head) {
		/* We cannot unmount now.. there are open files */

		fdbg("There are open files\n");
		ret = -EBUSY;
	} else {
		/* Unmount ... close the block driver */

		if (rm->rm_blkdriver) {
			struct inode *inode = rm->rm_blkdriver;
			if (inode) {
				if (inode->u.i_bops && inode->u.i_bops->close) {
					(void)inode->u.i_bops->close(inode);
				}

				/* We hold a reference to the block driver but should
				 * not but mucking with inodes in this context.  So, we will just return
				 * our contained reference to the block driver inode and let the umount
				 * logic dispose of it.
				 */

				if (blkdriver) {
					*blkdriver = inode;
				}
			}
		}

		/* Release the mountpoint private data */

		if (!rm->rm_xipbase && rm->rm_buffer) {
			kmm_free(rm->rm_buffer);
		}

		sem_destroy(&rm->rm_sem);
		kmm_free(rm);
		return OK;
	}

	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_statfs
 *
 * Description: Return filesystem statistics
 *
 ****************************************************************************/

static int romfs_statfs(FAR struct inode *mountpt, FAR struct statfs *buf)
{
	FAR struct romfs_mountpt_s *rm;
	int ret;

	fvdbg("Entry\n");

	/* Sanity checks */

	DEBUGASSERT(mountpt && mountpt->i_private);

	/* Get the mountpoint private data from the inode structure */

	rm = mountpt->i_private;

	/* Check if the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret < 0) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Fill in the statfs info */

	memset(buf, 0, sizeof(struct statfs));
	buf->f_type = ROMFS_MAGIC;

	/* We will claim that the optimal transfer size is the size of one sector */

	buf->f_bsize = rm->rm_hwsectorsize;

	/* Everything else follows in units of sectors */

	buf->f_blocks = SEC_NSECTORS(rm, rm->rm_volsize + SEC_NDXMASK(rm));
	buf->f_bfree = 0;
	buf->f_bavail = 0;
	buf->f_namelen = NAME_MAX;

	romfs_semgive(rm);
	return OK;

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Name: romfs_stat_common
 *
 * Description:
 *   Return information about a dentry - directory entry: file or directory
 *   Dentry is described by:
 *    * type (file or directory, access rights)
 *    * size
 *    * sectorsize (filesystem global)
 *  Resulting information is written into 'buf'
 *
 ****************************************************************************/

static int romfs_stat_common(uint8_t type, uint32_t size, uint16_t sectorsize, FAR struct stat *buf)
{
	memset(buf, 0, sizeof(struct stat));
	if (IS_DIRECTORY(type)) {
		/* It's a read-execute directory name */
		buf->st_mode = S_IFDIR | S_IROTH | S_IXOTH | S_IRGRP | S_IXGRP |
					   S_IRUSR | S_IXUSR;
	} else if (IS_FILE(type)) {
		/* It's a read-only file name */
		buf->st_mode = S_IFREG | S_IROTH | S_IRGRP | S_IRUSR;
		if (IS_EXECUTABLE(type)) {
			/* It's a read-execute file name */

			buf->st_mode |= S_IXOTH | S_IXGRP | S_IXUSR;
		}
	} else {
		/* Otherwise, pretend like the unsupported type does not exist */
		fdbg("Unsupported type: %d\n", type);
		return -ENOENT;
	}

	/* File/directory size, access block size */
	buf->st_size = size;
	buf->st_blksize = sectorsize;
	buf->st_blocks = (buf->st_size + sectorsize - 1) / sectorsize;
	return OK;
}

/****************************************************************************
 * Name: romfs_stat
 *
 * Description: Return information about a file or directory
 *
 ****************************************************************************/

static int romfs_stat(FAR struct inode *mountpt, FAR const char *relpath, FAR struct stat *buf)
{
	FAR struct romfs_mountpt_s *rm;
	FAR struct romfs_dirinfo_s dirinfo;
	uint8_t type;
	int ret;

	fvdbg("Entry\n");

	/* Sanity checks */

	DEBUGASSERT(mountpt && mountpt->i_private);
	DEBUGASSERT(buf != NULL);

	/* Get the mountpoint private data from the inode structure */

	rm = mountpt->i_private;

	/* Check if the mount is still healthy */

	romfs_semtake(rm);
	ret = romfs_checkmount(rm);
	if (ret != OK) {
		fdbg("romfs_checkmount failed: %d\n", ret);
		goto errout_with_semaphore;
	}

	/* Find the directory entry corresponding to relpath. */

	ret = romfs_finddirentry(rm, &dirinfo, relpath);

	/* If nothing was found, then we fail with EEXIST */

	if (ret < 0) {
		fvdbg("Failed to find directory: %d\n", ret);
		goto errout_with_semaphore;
	}

		/* It's a read-only directory name */

	type = (uint8_t)(dirinfo.rd_next & RFNEXT_ALLMODEMASK);
	ret  = romfs_stat_common(type, dirinfo.rd_size, rm->rm_hwsectorsize, buf);

errout_with_semaphore:
	romfs_semgive(rm);
	return ret;
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/
